Fixing device and heater used in fixing device

摘要

A heater used for a fixing device includes a substrate, first and second conductor patterns formed at either end of the substrate in the short direction of the substrate, a third conductor pattern formed between the first and second conductor patterns and separated from the two conductor patterns, a first heating member disposed between the first and third conductor patterns and electrically connected to the two conductor patterns, and a second heating member disposed between the second and third conductor patterns and electrically connected to the conductor patterns. The heater has both end regions in which the widths of the third conductor pattern in the short direction is smaller than that of a middle portion of the third conductor pattern. The widths of the first and second heating members in the end regions are smaller than the widths of the first and second heating members in the other region, respectively.

主权项

1. A heater for used in a fixing device that fixes a toner image onto a recording medium, comprising:
an elongated substrate; a first conductor pattern, extending in a longitude direction of the substrate, formed at one side of the substrate in a short direction of the substrate; a second conductor pattern, extending in the longitude direction, formed at the other side of the substrate; a third conductor pattern, extending in the longitude direction, formed between the first conductor pattern and the second conductor pattern, the third conductor pattern being separated from each of the first conductor pattern and the second conductor pattern; a first heat generating resistor electrically connected to the first conductor pattern and the third conductor pattern, the first heat generating resistor being disposed between the first conductor pattern and the third conductor pattern; and a second heat generating resistor electrically connected to the second conductor pattern and the third conductor pattern, the second heat generating resistor being disposed between the second conductor pattern and the third conductor pattern, wherein a width of the third conductor pattern, at an end region of the substrate in the longitude direction, is narrower than a width of the third conductor pattern at a center region of the substrate, and wherein a sum of a width of the first heat generating resistor and a width of the second heat generating resistor at the end region of the substrate is wider than a sum of a width of the first heat generating resistor and a width of the second heat generating resistor at the center region of the substrate.